POS1576-PARE IMPROVING METHOTREXATE PRESCRIBING AND DISPENSING SAFETY THROUGH A SIMPLE ADJUSTMENT TO ELECTRONIC PRESCRIBING.
Authors: C. Stovin, K. Lawan, C. Byrne, A. Choy, N. Purkayastha
Journal: Annals of the Rheumatic Diseases (2022)

Background Methotrexate (MTX) is the most commonly prescribed disease-modifying antirheumatic drug (DMARD) in rheumatoid arthritis, as well as being frequently used in other rheumatic conditions. Having been discovered in 1948 1 , its use is established and the toxicity profile is well recognised. In the rheumatology setting, it is prescribed as a once weekly dosing regimen. However, despite experience in the use of MTX, there still remains a concern for patient safety with regards to more frequent ingestion than the weekly dose. This can result in severe complications such as acute kidney injury, myelosuppression, mucositis and even death. According to Medicines and Healthcare products Regulatory Agency (MHRA), there were 11 adverse event reports between 2006 and 2020, and as a result, in 2020 the MHRA outlined guidance to reduce the potentially fatal dosing errors associated with the prescription of MTX 2 . Amongst this guidance, prescribers are instructed to discuss, document and include in the prescription, the specific day of the week MTX is to be taken. Dispensers are also advised to document the day of the week on the MTX drug dispensing label. At King’s College Hospital (KCH) there is an existing mandatory field for day of the week when prescribing inpatient non-cancer MTX treatment. However, this does not exist currently for outpatient electronic prescribing. Objectives To update practice in the KCH Rheumatology department, in line with MHRA guidance on MTX prescription. Methods A retrospective audit of 30 MTX new and renewal prescriptions over 1 month was conducted to assess concordance with MHRA guidance. The safety-nets of documentation of day of the week on most recent clinic letter, drug prescription and drug dispensing label were reviewed. Following this the electronic prescription system was updated to make “day of the week” a mandatory field required to complete MTX prescriptions. A sample of 30 patients post intervention was then re-audited. Results The percentage of new prescriptions across the 2 groups were roughly equivalent (30% vs 33%). Prior to intervention, 44% of new MTX prescriptions had no form of documentation of the day of the week across all 3 safety-nets, and only 33% had at least 2 of the 3 safety-nets completed. Post-intervention this has increased to 100%. Of those newly prescribed MTX, the inclusion of day of the week on clinic letters rose from 22% to 40%. There were similar improvements seen in safety-nets achieved for repeat prescriptions. Figure 1. Table 1. Percentage completed Pre-intervention Post-intervention New Renewal New Renewal Day of the week on letter 22% 43% 50% 45% Day of the week on prescription 33% 38% 100% 100% Day of the week on packaging 33% 71% 90% 100% None of the above 44% 14% 0% 0% At least 2 of 3 of the above 33% 52% 100% 100% All 3 completed 22% 14% 40% 45% Conclusion A significant improvement in concordance with MHRA guidance on MTX prescribing and dispensing can be easily achieved by making “the day of the week” a mandatory field to be included on all electronic MTX prescriptions. This change also produces a significant improvement in drug dispensing label safety and clinic letter documentation for patients newly initiated on MTX. References [1]Farber S, Diamond LK, Mercer RD, et al. Temporary remissions in acute leukaemia in children produced by folic acid antagonist, 4-aminopteroyl-glutamic acid (aminopterin) N Engl J Med. 1948;238:787–93. [2]MHRA. Methotrexate once-weekly for autoimmune diseases: new measures to reduce risk of fatal overdose due to inadvertent daily instead of weekly dosing. Published 23/9/2020. Disclosure of Interests None declared